The present invention relates to medical equipment and has particular reference to surgical suturing instruments. The disclosed instrument can find application for example in oncological practice for suturing the walls of the pharynx upon laryngectomy for cancer, as well as for suturing organs and tissues of the thoracic and abdominal cavities, e.g. for suturing pulmonary tissues.
Known in the art is a surgical suturing instrument, comprising a supporting body with a slot and a hook-shaped frame (cf. USSR Inventor's Certificate No. 125,523). The frame has a supporting jaw arranged transversely with respect to said slot and has an oblong flat area provided with depressions for staple legs to be bent. The slot in the supporting body opens in the direction parallel to the plane of the supporting body frame. Said slot accommodates a stapler body with the head into which a stapler magazine is inserted, said staple body being free to travel lengthwise in said slot. A staple ejector is housed in the stapler body with the capacity to traverse the stapler body. Because said slot in the supporting body is arranged with its open end in the direction parallel to the plane of the supporting body frame, the stapler body can be inserted into the slot and removed therefrom only in said direction.
When the stapler body is placed in the working position with respect to the supporting body, the gap between the supporting jaw and the staple magazine corresponds to the thickness of the tissues being sutured. When the stapler body is in the initial position, the stapler body can be inserted into the slot of the supporting body or withdrawn therefrom. To insert the stapler body into the slot of the supporting body in the initial position of the former more room than the above mentioned gap is needed in the direction of the plane of the frame.
The stapler body and the staple ejector are provided with corresponding actuators which traverse the supporting body towards the supporting jaw.
The staple magazine has open-end slots to accommodate metal staples therein. The slots are arranged in a strict correspondence with the depressions in the frame supporting jaw. The staple ejector has driving projections arranged correspondingly to the magazine slots. When the ejector moves towards the frame supporting jaw, its driving projections enter the magazine slots to eject the staples therefrom.
To prevent the tissue or organ being sutured from slipping off the instrument, the stapler head is provided with a fork limiter.
During suturing with the use of the above-discussed instrument, the tissue or organ being sutured is placed in between the flat area of the supporting jaw and the working end of the staple magazine facing said flat area. The tissue or organ being sutured may be placed into such a position by being introduced through the side opening of the hook-shaped frame. Then, the tissue or organ undergoing suturing is fixed in position by the fork limiter, whereupon the surgeon operates the actuator of the stapler body, thus positioning the magazine with respect to the supporting jaw of the supporting body such that the necessary suturing gap is established in between the flat area of the supporting jaw and the magazine. Next, the tissues are sutured by operating the staple ejector actuator, with the result that the ejector projections pass through the magazine slots and drive the staples out. The staple legs pierce the tissues being sutured and are thrust against the depressions in the flat area of the supporting jaw thereby bending and thus suturing the tissues. The tissue to be excised is out out, the magazine is withdrawn from the supporting jaw, and the instrument is removed from the operative wound.
However, the known instrument is inconvenient or impractical to be used for suture application in places of difficult accessibility or under specific conditions, where the space for manipulations involved in setting the instrument into the suturing position is limited, especially in the plane of the frame. This disadvantage is due to the construction of the supporting body of the instrument, wherein the supporting jaw of the supporting body and the staple magazine can be brought into position to the tissues being sutured, only through the side opening of the hook-shaped frame of the supporting body. For the supporting jaw and the staple magazine to be set into the suturing position using said technique, both of them must be moved with respect to the tissues undergoing suturing through a distance equal to the width of the supporting body frame. If the space in the operative wound proves to be insufficient, the surgeon has to perform complicated manipulations with the instrument to avoid any injury that is liable to be inflicted upon both the tissues being sutured and the surrounding tissues.
To cite an example, in the case of laryngectomy for cancer, by resorting to the known instrument, the frame supporting jaw and the staple magazine can be brought under the tumor to be excised to the place of suture application to the pharynx only from the direction of the chin or the breast which are located much superior to the place of suture application. Moreover, this involves some complicated tissue-injuring manipulations in a narrow space confined between the tumor resected on the side of the chin and in the region of the trachea, and the remaining organs and tissues of the patient's head and neck.
Another disadvantage inherent in the known instrument resides in large cross-sectional dimensions of the frame elements necessary for imparting reasonable rigidity to the construction of the instrument which has to sustain considerable loads resulting from staple deformation during suturing process. This feature restricts the field of application of the instrument. Thus, the application of the instrument involves relatively wide portions of the tissues being sutured which are required to be forced in between the frame supporting jaw and the staple magazine. This increases the distance from the line of staples of the suture to the plane of cut of the tissues and results in rougher suture scar. Additionally, a larger space is required between the tissues in order to initially position the supporting jaw and the side web of the supporting body frame. In some cases such favourable conditions cannot be provided and the apparatus is inapplicable.
To exemplify this statement, in the case of laryngectomy for cancer the cross-sectional dimension of the side web of the frame is too large and interferes with its positioning in the incision made in the tissues in the region of the chin or the trachea; the width of the supporting jaw is too large and makes it less practicable to place the jaw upon the healthy but narrow portions of the pharynx. This results in a reduced lumen of the sutured pharynx.
Simply reducing the cross-sectional dimensions of the frame elements of the supporting body makes it impossible to use the known instrument in any other application technique reasonable for the operation under discussion. For instance, the known instrument could be positioned, in principle, to the place of suture application from above (with respect to the patient in recumbent position) rather than from the chin or the breast, so as to pass the conglomerate of the tumor tissues through the gap between the supporting jaw and the magazine in the direction perpendicular to the plane of the frame. However, this cannot be carried out with the known instrument, since the distance from the supporting jaw to the magazine is much less than the size of the conglomerated tumor tissues. Therefore, the latter cannot be passed through the gap between the supporting jaw and the magazine. Any increase of said gap is self-defeating since it would necessitate an increase in the length of the side web of the supporting body hook and result in a reduced rigidity of the supporting body. Consequently, an inferior quality of sutures would result. To maintain adequate rigidity of the instrument in this case, it is necessary to increase the cross-sectional dimensions of the hook web which renders the known instrument still less applicable for the purpose.